Balanced-force rotary-cutting mechanism



Nov- 6, 1956 w. A. SPURRIER ET AL 2,769,494

BALANCED-FORCE ROTARY-CUTTING MECHANISM Filed June 24, 1954 States BALANCED-FORCE ROTARY-CUTTING MECHANISM William A. Spurrier and Russell K. Regler, Los Angeles, Calif.

7 Application June 24, 1954, Serial No. 438,908 4 Claims. Cl. 164-61) This invention relates to balanced-force rotary-cutting mechanisms and, more particularly, to balanced force rotary-cutting or shearing devices which may be utilized to trim paper or other material along a predetermined line; the trimming action being achieved by means of a balanced rotary scissors action making its possible to achieve a very precise cutting action while permitting accurate control of the paper or material to insure that the cutting is performed along the specified line.

The present invention is especially useful for trimming rolled stock or strips of paper or other material to a predetermined width, and may be utilized to trim parallel borders along rolled graph paper even though the original borders may not be parallel to lines on the graph paper.

Although many rotary-cutting devices have been previously devised, these devices may be conveniently separated into two general classes. In one class of cutting devices, the cutting edge is directly pressed against the material or paper to be trimmed, slit, or otherwise cut, the pressure of the cutting edge against the material being suflicient to provide the desired cutting action. This type of rotary-cutting device may be logically termed a .pressure-actuated cutting device. Typical examples of the pressure-actuated rotary-cutting devices may be found in U. S. Patent 2,467,700 dated April 19, 1949, to W. S. Riesenfeld, and in U. S. Patent No. 2,637,395 dated May 5, 1953, to O. Muller.

The principal disadvantage of the pressure-actuated rotary-cutting device is that a sharp, precise cut cannot be obtained since the cutting action itself requires that the material or paper be crushed at the cutting edge. Moreover, the direct pressure method either requires special metals in the cutting edge or will result in a reduced life of the cutting mechanism.

As a result of the recognition of the limitations of the pressure-actuated rotary-cutting devices, a second type of mechanism has been devised where two rotary-cutting ferred to as a scissors-action cutting device." Examples ,of this latter type of cutting device are found in U. S. .Patent 2,241,007 dated May 6, 1941, to B. M. Thomas;

U. S. Patent 2,571,201 dated Octover 16, 1951, to E. W. Clem; and U. S. Patent 2,627,922 dated February 10,

1953, to o. E. Teall.

or material to be trimmed. Thus, where it is necessary to carefully guide rolled stock or strips of paper along a predetermined cutting line, an unwanted force is introduced by the conventional cutting device which tends to draw the material along one of the cutting edges slightly so as to gradually move the rolled stock or strips of paper toward that cuttingedge.

Another disadvantage of the conventional scissors- 'action cutting device is that two specially-machined atent edges are utilized to obtain what may logically be re The scissors action itself introduces cutting wheels are required, whereas it will be shown that only a single cutting wheel need be machined, according to the present invention. Moreover, in utilizing two cutting wheels to obtain each rotary cutting action, the conventional practice is to utilize the rotary-cutting action to move the paper or material to be cut. This type of operation tends to reintroduce some of the undesirable features of the direct-pressure technique whereby the edge which is cut is somewhat distorted and is not as sharply cut as in cutting mechanisms of the present invention.

In the typical practice of the prior art such as is shown in patent to Stacy, No. 840,592, and to Powell, No. 1,804,642, the material or paper to be cut is driven by the same means utilized to provide the rotary cutting action. Thus in the device shown in the disclosure of Stacy the cutters 21 and 22 also feed the material (stamped sheets to be cut).

The prior art, therefore, cannot be utilized satisfactorily to trim paper or similar material along a predetermined line where it is necessary to achieve a very precise cutting action while permitting accurate and easy movement of the paper through the cutting edges along a specified line, which may vary considerably from a straight or linear direction. In a sense, the typical prior art referenced provides conflicting results. Where rotary balanced cutting devices are utilized, all movement of the paper or material to be cut in any direction other than a straight line-is prevented; and where nonlinear motion is possible, the prior art has failed to provide the necessary balanced rotary cutting action.

The present invention, on the other hand, obviates the above and other disadvantages of the prior art in providing a scissors-action rotary cutting mechanism where a double-edged rotary cutting wheel is utilized to provide balanced cutting action; and the cutting devices are in no way utilized to drive the paper or other similar material to be trimmed along predetermined boundaries.

According to another feature of the invention, a corresponding pair of second cutting edges related to the double-edge cutting discussed above are obtained as cutting grooves in a cutting roller which is also used to guide the material or paper to be trimmed or cut. The cutting grooves are quite easily machined into the cutting roller, as many grooves being introduced into the cutting roller as cutting positionsare desired.

' The double-edged cutting wheels are in no way utilized to drive the material to be cut since this action may be achieved by a separate drive wheel which presses the paper or material to be cut against the cutting roller. Thus, in this manner, the cutting roller may co-act with the drive wheel to provide the desired paper motion and at the same time, through the provision of cutting grooves therein, efiectively function as a series of sets of doubleedged cutting wheels.

Essentially the double-edged cutting action provided by the present invention may be considered as providing a balanced pair of rotary-scissors-like cutting edges which provide an extremely precise cutting action while introducing no undesirable paper or material motion.

Accordingly, it is an object ofthe present invention to provide an improved rotary-cutting mechanism wherein a precise scissors-action cutting may be performed without the introductionof unwanted cutting forces which interfere with the proper guidance of the material or paper to be cut. v i

Another object of the invention is to provide a rotarycutting device wherein only a single cutting wheel having a double cutting edge, is required for each cut to be performed; a corresponding set of cooperating cutting edges being obtained through a cutting roller which may also guide the paper or material to be cut.

' the cut-ting wheels; and

A further object of the invention is to provide a simple rotary trimmer wherein a sharp,-balanced cutting action is achieved by means of a double-edged cutting wheel cooperating with a correspondingpair of cutting grooves in a .cutting roller. 1 1 r Yet another object. of. the invention-is to providean may be obtained by means of ;a simple :cutting wheel mechanism without .the introduction of undesirable cutting forces.

An additional object'ofthe invention is to .pr'ovide a scissors-action rotary-cutting mechanism where-insubstantially no pressure is exerted upon the material.v to LbC cut by the cutting edges, assuring a precise, shar p cutting action.

p A more specific object of the invention is to provide an improved scrap pickofi device for a rotary cutting mechanism of the above-mentioned type whereby a minimum of adjustment is required toinsure the proper scrap removal. 7 r a t r The novel features which are believed to be characteristic of this invention, bothas to its organization and method of operation, together with further objects and advantages thereof, will the better understood from the following description considered in connection with the accompanying drawings in which one embodiment of the invention is illustrated by way of example. It is to be expressly understood, however, that the drawings are for the purpose of illustration and description only, and

are not intended as a definition of the limits of the invention. 7

' Figfllis a perspective overall;viewof ascissors-action V rotary-cutting device according to the present invention;

Fig. 2 is an enlarged rear perspective view of a portion-of the. embodiment of -Fig.xl-in the dire tion of arrow 2, showing in specific detail the double-edgedcub, ting wheel, the drive wheel, the grooved cutting roller,

and the paper scrap pick-oft fingersof Fig. l; V.

Fig; 3 is a sectional view taken along lines 13- 3 of j a Fig.2, indicating more precisely the cutting action'of Fig. 4 is another'partial'sectional cutting action, looking in thedirjection indicated in Fig. 3. Reference is now'made to Fig. 1 wherein one form of the rotaryrcutting mechanismaccording tothe present invention is shown; As indicated-inFigsl, the'esse'ntial features of the. invention include at least one double- A .eclgedicutting wheel 10, although two are shown in order view of the ;rotary-,

improved rotary trimmer wherein a-sharp vcutting edge 7 tures of the invention may be incorporated into a typical installation; Referring to 'Fig. 1, it is noted that the material M which may, for example, be rolled stock graph paper, rests on a paper receiving tray '50 and passes under an indicator bar and finger 6 which may be utilized as a guiding device to perform cuts along a predetermined.

line or a set of parallel lines. The paper or material M also passes under a paper tension bar 70 which aids in properly guidingmateria'l M around cutting roller 20. 7

It' will be noted that cutting wheel bar :12 is supported in a cut-ting wheel frame '80 which may be released from the main housing 9.0so that the cutting wheel positions. I may be readily adjusted or, 'if necessary, so that the cutting wheel bar 12" may be removed and cut-ting wheels or drive wheels added or subtracted'therefrom.

The particularly novel features of the invention are shown in more specific detail in Figs. 2, 3; and 4, where the cutting action 'of a single double-edged cutting wheel 7 v10 cooperating with a corresponding groove 21 is shown in enlarged detail. vReferring specifically to Fig. 2', it is noted that the double-edged cutting action of cutting wheel 'lfl co-a-cting with groove 2l inucutting roller 20 results in a strip S being cut from materialM. Theefact that a strip S is out through the rotaryacutting action,

according to the present invention, isicharacteristic since i itis by this means that the separate rotary-cutting forces of each edge of wheel 10 are balanced across strip: S. For simplicity, it may be stated that the rotary-cutting forces which normally would-move material M ;are balanced out across strip S. Asa result of this character istic strip-cutting action, the embodiments of the present invention require some means for removing the scrap strip from groove21 to prevent hinderance of subsequent cutting. This scrap. strip removal is .eflected'quite simply means of scrap pick-ofi fingers 100, eaeh finger being essentially a spring wire embedded in. axorresponding groove 21 and extending therefrom to .a scrap receiving chamber 110 inmain housingl90r While theinvention'is not 'li .ty'peaof piekotr fingers or wires, noveltfeatures are'pro vided .rthereby which will now be described. It willlbe noted in Figs. 2 and 3 thateach pickofif 'wir e 10ll in cludes .a' first portion which is .rcurved to the samedia'meter astherinter-diameterof the. groove in the wcutt ing roller. An opening is left in this firs-t portion which will to illustrate thefmanner in which parallel; lines ,may'lbe cut on graph paper. A balanced, doubleredged ,rotarya cutting action'is 'obtained by means of'theIco-aetidri of 'cutting wheel 10 and the cutting groove '21 in; a cutting" roller 20. It be notedthat several cutting grooves 21 are included in roller 20 so that anygnumber of cutting wheels '10, may be included as desired,oraparticular wheel 10 may be'moved along cutting 'whee'l bar tra n) the desired cutting position.

The other improved feature of the invention to be "especially noted Fig. '1 is that cutting roller 20 also 7 guides the paper or other ,materialM to be cut, the driv- 'ing force being jobtained' by means of'a conventional. motor and pulley 'arrangement- 30 and the 'coaction with at least one drive wheel.-40. Thus,1it is apparentthat.

the cuttingroller -20 not only provides a pair of cutting tedges "cooperating with those of .a corresponding-cutting wheel 10, .but also guides thelmaterial i against by drive wheel 40, A-gain, noted that. three drive wheels 40' are-shown,- although anynumber. maybe utilized, depending upon the particular operation 7 contemplated.

pressed there- In 'so'me "applications, f or example, 1 .a single center driving wheel may be 'sufiicient. 1

"The features of, the embodiment pfjdgmlf-thusjfar 7 described are essential toithe -invention pnd, theref0if have'been enumeratedatthe outset, The remainingfistrue p ture be -descrihed,-however; 'irrorder to'. ,more; rparlieu-131115! Point G1 9.mennee gwhichf he bas s allow the spring to be. forced over thecutting groove and then through its spring action, towrapitself around i .the cutting groove proyiding frictional'engagement there-J with. r A

'As. the putting rolleris the second. portion I the spring wire is. forced against. the gscrapi receiving chambrdlO so that the cuttingl groove {thenslipsin rota-Q Etion inside the first portion ofthe; spring wire, manner, .the pickofij fingers ltlfi maylae simply inserted ,in the cutting grooves and need not'fb e. adjusted in place ;since the'rotation of the cuttingroller holds them positionasrequired.

rotarys'cissiorsicutting,

, 1 Thus, it is .not ,considfred necessary ito point antenna mechanical. features of the embodiment shown; I For exf" p 'ample,3 a particular mounting-arrangement,is shown jo'rfij icutting 'Wheels' in! so ,tha' li v may bejrelea fro qcutting wheel been were sud along manrde ired cu -1 .tingpositioncooperating with a vcorresponding'{cutting groove 21; 'Ina" similarjmanner, arrangement is rnade so that drivin g'wheels '40 may beadjustedtothedesired l' ime atin ro ttqn- Eu-rtber meia rw liaWi em:er-J' mited to the articular rangement is shown for securely fastening cutting wheel frame 80 to main housing 90. This has not been specifically described since it is assumed to be a conventional technique.

However, the following constructional features have been described and are believed to be of the essence. First, the cutting action is a double-edged, balanced r tary-scissors action. It is achieved by means of cooperation between a wheel of the general type and a cutting groove in a cutting roller which also guides the material to be cut. As has been previously pointed out, this arrangement obviates the necessity for a pair of cutting wheels for each cut and provides a simple expedient for obtaining the equivalent of a corresponding pair of cutting edges for each cutting wheel by means of simplymachine grooves in a cutting roller.

As a result of the characteristic cutting action of embodiments of the invention, it has been pointed out that some means is required to remove the scrap strip from the cutting groove. This is achieved in a specific simple manner in the particular embodiment illustrated. However, it will be understood that the basic concept of the invention is not limited to the particular scrap strip removing technique shown. It may be possible, for example, to remove the scrap by means of air pressure or other extraction means. It has been pointed out that the invention may be used in cutting a wide variety of material and does not require any fixed number of cutting and driving wheels or of corresponding cutting grooves.

The modifications herein suggested are by no means intended to be exclusive since other such modifications will be apparent to those skilled in the art.

What is claimed as new is:

1. In a rotary cutting mechanism for trimming paper or other similar material, wherein a double-edged rotatable cutting device is operated cooperatively with a rotatable cutting roller, said roller including a cutting groove having two edges cooperatively associated with the edges of said rotary cutting device, the material to be trimmed being passed through the rotatable cutting device to a receiving surface; a device for removing scrap material from said cutting groove, said device comprising: a spring wire including first and second portions having opposite curvatures, said first portion being of substantially the same circular curvature as the inner edge of said cutting groove, including an opening allowing the entry of said cutting groove therein, and having a spring constant such that the insertion of said first portion around said cutting groove causes a frictional engagement therewith; and said second portion being arranged to engage said surface whereby the insertion of said first portion around said cutting groove, and the rotation of said roller causes said spring wire to engage said surface and to provide a scrap removable path for said material.

2. In a rotary cutting system for trimming paper or other material along predetermined borderlines, the combination comprising: first and second double-edged cutting wheels; a cutting roller including first and second grooves cooperatively associated with said cutting wheels, respectively, to provide two pairs of cutting edges; a driving wheel attached for rotation with said cutting wheels and for engagement with said roller, the paper or material to be cut being entered between said driving wheel and said cutting roller and driven through said pairs of cutting edges; a shelf for receiving said material as it is passed between said driving wheel and said cutting roller; and a pair of spring pickotf wires, one for each of said cutting grooves, each of said wires including a head section adapted to be inserted around the associated cutting groove to provide frictional engagement therewith and a tail adapted to engage said shelf to inhibit movement of said wire, whereby said pickoif wire may be snapped onto by said cutting groove and is self-positioning as said cutting roller is rotated.

3. A border trimming mechanism for roll-stock ma,- terial comprising: a cutting wheel bar; first and second cutting wheels mounted on said bar, said wheels being spaced by an amount corresponding to the desired width for said roll-stock paper, after trimming, each of said Wheels having parallel cutting edges; a cutting roller,

parallel to said bar and including a cutting groove for each of said Wheels, each groove forming a pair of trimming edges in cooperation with the associated wheel; a driving roller mounted on said bar adapted for cooperation with said roller for driving said material into said trimming edges; a receiving shelf for said material as it passes through said trimming edges; first and second pickoif wires each including a circular head having substantially the same diameter as the interdiameter of said cutting grooves and an opening allowing the insertion of said pickoif wires around said cutting grooves, respectively, said head having a spring action resulting in a frictional engagement with the associated cutting groove, and each pickotf wire including a tail arranged for engagement with said receiving shelf to position said pickofi wire for removal of scrap material.

4. A rotary trimming device for cutting parallel borders along roll-stock material, said device comprising: a driving shaft; first and second double-edged rotary cutters mounted on said shaft at points separated by the desired distance between said parallel borders; a cutting roller including two cutting grooves positioned for cooperation with said rotary cutters, respectively; a driving roller mounted upon said shaft and rotatable therewith for engaging said cutting roller during the rotation thereof; a surface for receiving said material as driven between said driving roller and said cutting roller; and first and second pickofi fingers, each of said fingers having a first circular portion for frictionally engaging the inter-diameter of said grooves, respectively, and a second portion for engaging said receiving surface as said cutting roller is rotated.

References Cited in the file of this patent UNITED STATES PATENTS 310,534 Murray Jan. 6, 1885 a 459,920 Wright Sept. 22, 1891 595,092 Basley Dec. 7, 1897 740,201 Stimpson Sept. 29, 1903 801,916 Rudolphi Oct. 17, 1905 840,592 Stacy Jan. 8, 1907 1,804,642 Powell May 12, 1931 1,866,941 Peters July 12, 1932 2,039,831 Page May 5, 1936 2,241,395 Egling May 13, 1941 

